1YKG:
reference: Solution Structure of the Sulfite Reductase Flavodoxin-like Domain from Escherichia coli(,)., Sibille N, Blackledge M, Brutscher B, Coves J, Bersch B, Biochemistry 2005 Jun 28;44(25):9086-95. PMID: 15966732

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).